Missing items

I was really hoping that it wouldn't come to this as I've never had a problem with ordering online but with my emails going unanswered, I had no choice...

I placed an order with Mr price on 28/06/2020 which was delivered yesterday 07/07/2020 only to find that 2 of the items weren't in the package. On the invoice I received it shows the 2 items but quantity and price says 0...

My order was as follows : 2x tube jeans 3x fluffy cable pul*****s which were on special for R120 each (saving R200) 1x poplin shirt I also received R100 off at that time for placing an order over R500.... Totaling to R 784. 97 after discount (including delivery)...

Now what I don't understand is, The invoice that I received with my package states a different total which is less than what I paid. I didn't receive 2 of the items order And I paid full price for 1 of the fluffy cable pul*****s which was meant to be on special for R120...

So now I'm in a situation where I don't have 2 items that I paid for and Mr price owes me money...